Abstract: In the present study, the metabolite profiles of procyanidin B2 in the plasma, liver, heart, spleen, lung, kidney, brain and small intestine of mice were qualitatively evaluated by high performance liquid chromatography with diode array detector coupled with electrospray ionization ion trap time-of-flight multistage mass spectrometry (HPLC-DAD-ESI-ITTOF-MSn). The results showed that the major conjugated metabolites included methylation metabolites (8), sulfonation metabolites (7), hydration metabolites (5) and hydroxylation metabolites (1), glucuronidation metabolite (1). Procyanidin B2 was metabolized into 6, 8, 8, 6, 3, 6, 2 and 2 forms in plasma, liver, small intestine, kidney, lung, heart, brain and spleen, respectively; three forms of identified metabolites were found with cleavage of interflavanic bond. The conjugated metabolites of procyanidin B2 were diverse and distributed widely in various tissues of mice. Methylation metabolites, sulfonation metabolites and hydration metabolites were dominant, and the liver was the main organ for the conjugated metabolites of procyanidin B2 according to product formation (Mr＞577.13). The cleavage of interflavanic bond reaction was an important way that procyanidin B2 is absorbed.

Key words: procyanidin B2, HPLC-DAD-ESI-IT-TOF-MSn, metabolites, tissue distribution